Network Rail staff face losing their jobs if they live more than 75 minutes' travelling time from the firm's new offices, the TSSA union warned today.
The union said hundreds of Network Rail employees could be made redundant if they cannot get to the new headquarters in Milton Keynes, Buckinghamshire, on time.
TSSA has calculated that 850 staff, mainly living south of London in Kent, Surrey, Sussex and Hampshire, will be affected by the "unfair" decision.
The new office is set to open in the summer, replacing the current London headquarters of the rail infrastructure company.
TSSA general secretary Manuel Cortes said: "This is an unfair and arbitrary decision which we believe to be unlawful. This modern-day version of Beat the Clock to get work is a complete nonsense."
Mr Cortes has written to Network Rail warning bosses that the union will take legal action to defend its members, adding: "We are hoping that NR will start to see sense on this issue."
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